Bone suture assembly

ABSTRACT

The present invention provides an internal fracture fixation assembly for fixation of a fracture in a bone. The assembly includes an implantable first suture retaining member having a body configured and dimensioned to be positionable proximate an outer surface of the bone on a first side of the fracture. First and second parallel channels extend through the first suture retaining member. The assembly also includes a suture. A first portion of the suture extends through the first channel of the first suture retaining member, while a second portion of the suture extends through the second channel. At least one of the portions of the suture is positioned in the bone. Furthermore, the assembly includes an implantable second suture retaining member having a body configured and dimensioned to be positionable proximate the outer surface of the bone on a second side of the fracture. A first channel extends through the second suture retaining member. The first channel receives at least one of the portions of the suture.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No. 10/685,117 filed Oct. 14, 2003. The aforementioned application Ser. No. 10/685,117 is itself a continuation of Ser. No. 09/835,473 filed Apr. 16, 2001, now U.S. Pat. No. 6,638,279. The aforementioned application Ser. No. 09/835,473 is itself a continuation of U.S. patent application Ser. No. 09/532,942 filed Mar. 22, 2000, now U.S. Pat. No. 6,238,395. The aforementioned application Ser. No. 09/532,942 is itself a continuation of U.S. patent application Ser. No. 09/363,707 filed Jul. 29, 1999, now U.S. Pat. No. 6,045,551. The aforementioned application Ser. No. 09/363,707 is itself a continuation-in-part of U.S. patent application Ser. No. 09/323,488 filed Jun. 1, 1999, now U.S. Pat. No. 6,117,160. The aforementioned application Ser. No. 09/323,488 is itself a continuation of U.S. patent application Ser. No. 09/019,977 filed Feb. 6, 1998, now U.S. Pat. No. 5,921,986. The benefit of the earlier filing dates of the aforementioned applications and patents is claimed.

BACKGROUND OF THE INVENTION

The present invention relates to a new and improved method and apparatus for securing sections of a fractured bone and/or securing body tissue to bone.

When a bone is broken or fractured, it is necessary to press sections of the bone on opposite sides of the fracture together in order to promote healing of the bone. Bone screws have been used with or without metal plates to hold the sections of the fractured bone against movement relative to each other. In addition, it has been suggested that avulsion fractures could be treated by using wire sutures between sections of bone in a matter similar to that disclosed in U.S. Pat. No. 5,474,554. It has also been suggested that an anchor could be retained in a bone is a manner disclosed in U.S. Pat. Nos. 5,527,343 and 5,534,012.

SUMMARY OF THE INVENTION

The present invention relates to a method of securing sections of a fractured bone. Sections of a fractured bone are held against movement relative to each other.

In accordance with one aspect of the present invention, there is provided a bone suture assembly for treating a fracture of a bone. The bone suture assembly includes a first bone plate positioned proximate to the bone and a suture positioned through the first bone plate and across the fracture of the bone to thereby stabilize the fracture. The suture assembly may include a second bone plate positioned proximate to the bone generally opposite the first bone plate. The suture may be positioned through the second bone plate to stabilize the fracture. The suture assembly may also include a passage through the bone and across the fracture, wherein the suture is disposed within the passage. The passage may be nonlinear and may include a tubular member. The suture may be disposed within the tubular member.

Furthermore, the bone suture assembly may include at least one fastener to hold the first bone plate to the bone. At least one fastener may extend across the fracture of the bone and may extend through the bone and through the second bone plate. At least one fastener may also include a screw and nut. Additionally, the suture assembly may include a tubular member in the bone positioned across the fracture, and the suture may be disposed within the tubular member. The tubular member may be packed with bone particles or bone osteoinductive protein.

In accordance with another aspect of the present invention, the bone suture assembly includes a first suture anchor positioned proximate to the bone, a first bone plate positioned between the first suture anchor and the bone, and a suture positioned across the fracture of the bone to stabilize the fracture. The suture has a first end portion disposed through the bone plate and attached to the first suture anchor. The suture assembly may also include a second suture anchor positioned proximate to the bone generally opposite the first suture anchor. The second suture anchor may be attached to a second end portion of the suture.

Moreover, the bone suture assembly may include a second bone plate positioned between the second suture anchor and the bone. The suture assembly may also include a passage through the bone and across the fracture, wherein the suture is disposed within the passage. In the present invention, the first and second suture anchors may be suture retainers which may have deformable material to hold the suture retainers to the suture.

In accordance with still another aspect of the present invention, a method for treating a fracture of a bone is provided. The method includes positioning at least one suture anchor proximate to the bone, positioning at least one bone plate between at least one suture anchor and the bone, and moving at least one suture across the fracture of the bone and through at least one bone plate. The method also includes attaching at least one suture to at least one suture anchor and tensioning at least one suture to stabilize the fracture of the bone. At least one suture anchor may be a suture retainer.

In addition, the method may include fastening at least one bone plate to the bone with at least one screw. At least one screw may have a length less than the diameter of the bone, and at least one screw may have a length greater than the diameter of the bone. At least one screw may include at least one nut, and at least one screw may extend across the fracture of the bone.

Furthermore, the method may include forming at least one passage through the bone and moving at least one suture through at least one passage. Also, at least one suture attached to at least one suture anchor may be moved through at least one passage. The method may also include changing the orientation of at least one suture anchor from a first to a second configuration thereby causing at least one suture anchor to become proximate to the bone and impassable through at least one passage. Finally, the method may include tensioning at least one suture between at least two suture anchors to stabilize the fracture of the bone.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the invention will become more apparent upon a consideration of the following description taken in connection with the accompanying drawings wherein:

FIG. 1 is a schematic illustration of a bone having a fracture which has been treated with sutures and suture anchors;

FIG. 2 is an enlarged fragmentary schematic sectional view of a portion of the bone of FIG. 1 and illustrating the manner in which a suture extends across the fracture and interconnects suture anchors on opposite sides of the fracture;

FIG. 3 is a schematic illustration, generally similar to FIG. 2, illustrating the manner in which a suture retainer is used to maintain tension in a suture which extends across a fracture to a suture anchor;

FIG. 4 is a schematic illustration, generally similar to FIGS. 2 and 3, illustrating the manner in which body tissue is connected with a bone using a suture and suture anchors;

FIG. 5 is a schematic illustration, generally similar to FIGS. 2–4, illustrating the manner in which a suture extends between suture anchors through a nonlinear passage;

FIG. 6 is a schematic illustration, generally similar to FIG. 5, illustrating the manner in which a suture extends between a suture anchor and a suture retainer through a nonlinear passage;

FIG. 7 is a schematic illustration depicting a bone which has been fractured in such a manner as to have a bone fragment connected with the bone by muscle or other fibrous tissue;

FIG. 8 is a schematic illustration depicting the manner in which the bone fragment of FIG. 7 is connected to the bone by a suture and a pair of suture anchors;

FIG. 9 is a schematic illustration depicting the manner in which a bone fragment is connected with a bone by a suture which extends between an anchor within the bone and an anchor which engages the bone fragment;

FIG. 10 is a schematic illustration, generally similar to FIGS. 2–4, illustrating in the manner in which plates and rigid fasteners are used in association with a suture and anchors to treat a bone fracture;

FIG. 11 is a schematic illustration depicting the manner in which a thin elongated member is moved through bone and the manner in which a drill is moved along the thin elongated member to enlarge a passage formed in the bone by the thin elongated member;

FIG. 12 is a schematic illustration depicting the manner in which an anchor is moved through a passage in the drill of FIG. 11 after the thin elongated member has been removed from the passage in the drill;

FIG. 13 is a schematic illustration, generally similar to FIG. 2, illustrating the manner in which a tubular member is positioned in a passage in the bone;

FIG. 14 is a schematic illustration, generally similar to FIG. 5, illustrating the manner in which tubular members are positioned in a nonlinear passage in a bone; and

FIG. 15 is a schematic illustration, generally similar to FIG. 3, illustrating the manner in which a suture retainer is used with a tubular member which is positioned in a passage in a bone.

DETAILED DESCRIPTION OF THE INVENTION

A bone 20 which has been fractured is illustrated in FIG. 1. The bone 20 is divided into two sections 22 and 24 by a fracture 26. Opposite side surfaces 28 and 30 of the fracture 26 are pressed together by bone suture assemblies 32.

It should be understood that the bone suture assemblies 32 may be utilized in the treatment of any one of many different types of fractures. The fractures may or may not result in the formation of one or more bone fragments. In FIG. 1, the bone suture assemblies 32 have been illustrated as interconnecting sections 22 and 24 of a complete bone fracture of the spiral type. However, the bone suture assemblies 32 could be utilized to connect a fragment of a bone to the main portion of the bone from which the fragment was broken off.

Each of the bone suture assemblies 32 has the same construction. However, the bone suture assemblies 32 could have different constructions if desired. The construction of one of the identical bone suture assemblies 32 is illustrated in FIG. 2.

The bone suture assembly 32 (FIG. 2) includes a flexible suture 38 which extends across the fracture 26. The suture 38 is disposed in a straight cylindrical passage 40 which extends diametrically across a generally cylindrical portion of the bone 20. The passage 40 extends through hard compact tissue of an outer layer 42 of the bone and through spongy or cancellous bone tissue 44 which is enclosed by the hard outer layer. Although the passage 40 has a linear configuration, the passage could have a nonlinear configuration if desired.

The suture 38 extends between a first suture anchor 50 disposed on one side of the fracture 26 and a second suture anchor 52 disposed on the opposite side of the fracture. Tension is maintained in the suture 38 to press the suture anchors 50 and 52 against opposite sides of the bone 20 with a predetermined force. This force presses the side surfaces 28 and 30 of the fracture 26 firmly together to promote healing of the fracture. If desired, buttons or other force distributing members could be provided between the anchors 50 and 52 and the bone 20. Body tissue could be disposed between the anchors 50 and 52 and the bone 20.

The suture 38 and/or suture anchors 50 and 52 may be formed of any desired natural or artificial material. For example, the suture 38 may formed of either a polymeric material or a metal. The suture 38 may be biodegradable. Any known suture material may be utilized to form the suture 38.

The suture anchors 50 and 52 have the same construction. However, the anchor 50 could have a construction which is different than the construction of the anchor 52. The anchor 50 has a cylindrical outer side surface 56 which extends between smooth rounded end portions 58 and 60. A pair of parallel cylindrical openings 64 and 66 extends diametrically through the anchor 50. The anchor 50 is free of sharp corners or projections to avoid cutting or abrading of body tissue disposed adjacent to the anchor.

The suture anchor 50 is made of a biocompatible material. Suitable materials include stainless steel or titanium, cobalt chrome and other biocompatible metals. Polymeric material may also be used, suitable polymeric materials includes polyethylene, polypropylene, and biodegradable material such as PLA and PGA. It is believed that it may be preferred to form the suture anchors 50 and 52 from biodegradable or bioerodible copolymers. If desired, the anchor 50 could be formed of body material or hydrophilic materials.

It is contemplated that the anchor 50 may have any desired configuration. For example, the anchor 50 could have any one of the configurations disclosed in U.S. Pat. No. 5,522,846 issued Jun. 4, 1996 and entitled “Suture Anchor”. Alternatively, the suture anchor 50 could have the configuration disclosed in U.S. Pat. No. 5,534,012 issued Jul. 9, 1996 and entitled “Method and Apparatus for Anchoring a Suture”.

Although the anchor 50 may have any desired configuration, the cross-sectional size of the anchor is such as to enable the anchor to be moved through the passage 40. In addition, the length of the anchor 50 is such as to enable it to span an opening at an end of the passage 40 and transmit force from the suture 38 to a substantial area on the outer layer 42 of the bone 20. It is believed that it will be preferred to form the anchor 50 in such a manner as to eliminate any sharp corners or projections.

In the illustrated embodiment of the invention, the anchor 50 has a cylindrical configuration. This particular anchor has an axial length of about two millimeters and a diameter of about one millimeter. The length of the anchor 50 may be approximately three times the diameter of the anchor. The openings 64 and 66 have a diameter of about one-half millimeter.

It should be understood that the foregoing dimensions have been set forth herein for purposes of clarity of description and it is contemplated that the size of the anchor 50 may vary as a function of the size of the bone being treated. Thus, relatively small anchors may be used in association with treatment of small bones in a wrist, hand, foot or ankle of a patient. Relatively large anchors may be used in association with treatment of larger bones in an arm, shoulder, leg or hip of a patient. It should be understood that the bone suture assembly 32 may be used in conjunction with many different bones other than the specific bones previously mentioned.

Only a single anchor 50 or 52 has been shown at opposite ends of the passage 40. It is contemplated that a plurality of anchors could be provided at each end of the passage 40. For example, a pair of separate or interconnected anchors could be provided in a manner similar to that disclosed in the aforementioned U.S. Pat. No. 5,534,012.

In the embodiment of the invention illustrated in FIG. 2, the suture 38 has a pair of limbs or sections 72 and 74 which extend through the openings 64 and 66 in the suture anchors 50 and 52. A connector section 76 interconnects the two limbs 72 and 74 of the suture 38 and engages a portion of the anchor 50. A knot 78 is formed in the opposite ends of the limbs 72 and 74 to interconnect the two limbs of the suture 38.

When the knot 78 is formed, a predetermined tension is present in the limbs 72 and 74 of the suture 38. This results in the suture anchors 50 and 52 being pressed firmly against the bone 20 with a predetermined force. This predetermined force is maintained during and after tying of the knot 78.

When the bone suture assembly 32 is to be used to treat the fracture 26 in the bone 20, the two sections 22 and 24 of the bone are pressed together at the fracture 26 to align the side surfaces 28 and 30 of the fracture. A drill is then used to form the passage 40 which extends diametrically through the generally cylindrical bone 20. Of course, the passage 40 could be formed by the use of a tool other than a drill. If desired, the passage 40 could have a noncircular cross-sectional configuration.

Once the passage 40 has been formed in the two sections 22 and 24 of the bone 20, a tubular cylindrical member is inserted into the passage 40 and extends diametrically through the bone 20. The leading end of the tubular cylindrical member is aligned with a circular outlet 84 from the passage 40. The opposite end of the tubular member is aligned with a circular inlet 86 to the passage 40. The tubular member has a thin cylindrical wall which engages the sections 22 and 24 of the bone 20. A cylindrical inner side surface of the tubular member defines a passage having a diameter which is only slightly less than the diameter of the passage 40.

By inserting the tubular member into the passage 40, the portions of the passage disposed on opposite sides of the fracture 26 are maintained in alignment. The tubular member may be flexible to enable the tubular member to be inserted into a nonlinear passage 40 through the bone 20. The tubular member may be formed of metal or a polymeric material. If the tubular member is formed of a polymeric material, it may be preferred to form the tubular member from a biodegradable or bioerodible copolymer.

The suture 38 is formed into a loop which extends through the openings 64 and 66 in the anchor 50. At this time, the suture 38 has a length which is substantially greater than the length illustrated in FIG. 2. The cylindrical anchor 50, with the suture 38 connected thereto, is then positioned in axial alignment with the tubular member which extends through the passage 40. Thus, the anchor 50 is moved to an orientation in which a longitudinal central axis of the anchor is coincident with the longitudinal central axis of the cylindrical passage in the tubular member which extends through the passage 40 in the bone 20.

The leading end 58 of the anchor 50 is then moved into the cylindrical tubular member which forms a liner for the passage 40. A pusher member pushes the anchor 50 from an upper (as viewed in FIG. 2) end of the tubular member along the passage 40 in the bone 20 and through the outlet 84 from the passage. As the anchor 50 moves through the passage 40, the suture 38 is pulled through the passage 40 by the anchor.

The orientation of the anchor 50 is then changed from an orientation in which the longitudinal central axis of the anchor 50 is aligned with the longitudinal central axis of the passage 40 to an orientation in which the longitudinal central axis of the anchor 50 extends generally perpendicular to the longitudinal central axis of the passage 40, i.e., the orientation shown in FIG. 2. To pivot the anchor 50 to the orientation shown in FIG. 2, as the anchor emerges from the outlet 84, the suture 38 is tensioned. The combination of the tension in the suture 38 and force applied against the trailing end 60 of the anchor by the pusher member causes the anchor to pivot about the trailing end 60 of the anchor. The pusher member is then withdrawn and the suture tensioned to move the anchor to the position shown in FIG. 2 in a manner similar to that described in the aforementioned U.S. Pat. Nos. 5,527,343 and 5,534,012.

Although it is believed that it may be preferred to change the orientation of the anchor 50 after it has emerged from the passage 40, the anchor could be blocked from reentering the passage in other ways if desired. Thus, the anchor could expand after emerging from the passage 40. This could be accomplished by having spring biased arms held in a retracted position by engagement of spring biased arms with the inner side surface of the tubular cylindrical member which lines the passage 40. Upon emerging from the passage, the arms would move outward under the influence of spring forces and extend radially outward beyond the edge of the exit from the passage 40. If desired, the anchor 50 could be constructed so as to expand in a manner similar to that disclosed in U.S. Pat. No. 5,397,331 and/or U.S. Pat. No. 4,409,974.

Rather than expanding under the influence of stored energy, such as spring force, the anchor 50 could expand by absorbing body fluids. Thus, the anchor 50 may be compressed when it moves through the passage 40 and will expand and absorb body fluids after emerging from the passage 40. It is contemplated that the anchor 50 could be constructed so as to expand in any one of the ways disclosed in U.S. patent application Ser. No. 08/699,553 filed Aug. 19, 1996 by Peter M. Bonutti and entitled “Suture Anchor”.

The cylindrical tubular member is then withdrawn from the passage 40. It should be understood that the cylindrical tubular member is used to line the passage 40 in the bone 20 during movement of the anchor 50 through the passage. The use of the tubular member to line the passage 40 may be omitted if desired. However, if the use of the tubular member to line the passage 40 is omitted, the anchor 50 and pusher member would be exposed to the cancellous bone tissue 44 during movement of the anchor through the passage.

The limbs 72 and 74 of the suture 38 are then threaded through openings 64 and 66 in the second suture anchor 52. The limbs 72 and 74 of the suture 38 are tensioned and the second anchor 52 is pressed against the outer side surface of the bone 20. While a predetermined tension force is maintained in the limbs 72 and 74 of the suture 38, the knot 78 is tied in the suture to interconnect the two suture anchors 50 and 52 with the suture 38. The suture 38 is then trimmed to the desired length.

Once the knot 78 has been tied between the limbs 72 and 74 of the suture 38, the tension in the suture 38 presses the side surfaces 28 and 30 of the fracture 26 together. This pressure between the side surfaces 28 and 30 of the fracture 26 is maintained by the suture 38 and suture anchors 50 and 52 until the fracture heals. It is believed that it may be preferred to form the suture 38 and suture anchors 50 and 52 of a biodegradable material which, after the fracture 26 has healed, will dissolve in the patient's body.

The cylindrical tubular member which is inserted into the passage 40 through the bone 20 performs the dual functions of lining the inside of the passage 40 and maintaining the two sections 22 and 24 of the bone in alignment. The cylindrical tubular member could have a slot formed in a side wall of the tubular member to facilitate insertion of the tubular member into the passage 40. It is contemplated that the cylindrical tubular member could be left in the passage 40 after the bone suture assembly 32 has been installed. If the slotted or unslotted cylindrical tubular member is to be left in the passage 40, the cylindrical tubular member may be formed of a biodegradable or bioerodible copolymer. When the cylindrical tubular member remains in the passage 40, the suture 38 extends through the tubular member.

Although only a knot 78 has been shown in FIG. 2 adjacent to the second anchor 52, a suture retainer could be provided to further hold the limbs 72 and 74 of the suture 38. If a suture retainer is to be used in association with the knot 78, the suture retainer will be moved along the limbs of the suture 38 toward the knot before the limbs 72 and 74 of the suture are trimmed to the short length shown in FIG. 2. The suture retainer would then be plastically deformed to grip the limbs 72 and 74 of the suture 38. Thereafter, the suture limbs 72 and 74 would be trimmed to a desired length.

Bone Suture Assembly—Second Embodiment

In the embodiment of the invention illustrated in FIG. 2, a pair of suture anchors 50 and 52 are connected with the suture 38 to maintain tension in the suture and pressure against opposite side surfaces 28 and 30 of the fracture 26. In the embodiment of the invention illustrated in FIG. 3, a suture retainer is used in place of one of the suture anchors. Since the embodiment of the invention illustrated in FIG. 3 is generally similar to the embodiment of the invention illustrated in FIG. 2, similar numerals will be utilized to designate similar components, the suffix letter “a” being associated with the embodiment of the invention illustrated in FIG. 3 to avoid confusion.

A bone 20 a has sections 22 a and 24 a which are separated by a fracture 26 a. The fracture 26 a has side surfaces 28 a and 30 a which are pressed together by a bone suture assembly 32 a. A suture 38 a extends through a cylindrical passage 40 a which extends diametrically through the generally cylindrical bone 20 a. The suture 38 a has a pair of limbs or sections 72 a and 74 a which are connected with a suture anchor 50 a. The suture anchor 50 a has the same construction as the suture anchor 50 of FIG. 2.

In accordance with a feature of this embodiment of the invention, a suture retainer 92 is used in place of the suture anchor 52 of FIG. 2. The suture retainer 92 has a spherical configuration. A cylindrical passage 94 extends through the center of the spherical suture retainer 92. The sections 72 a and 74 a of the suture 38 a extend around the spherical outer side surface of the suture retainer 92. Thus, a loop is formed in each of the sections 72 a and 74 a around portions of the suture retainer 92.

If desired, the suture retainer 92 could have a different configuration. For example, the suture retainer 92 could have an oval or elliptical configuration. Although the passage 94 has a linear central axis, the passage could have a nonlinear central axis. If desired, a plurality of passages having the same or different configurations could be provided in the suture retainer 92.

After the suture 38 a has been inserted through the suture retainer 92, in the manner illustrated schematically in FIG. 3, the suture retainer 92 is moved along the sections 72 a and 74 a of the suture 38 a toward the bone 20 a. The suture retainer 92 is formed as one piece of a polymeric material having a relatively low coefficient friction. Therefore, the two sections 72 a and 74 a of the suture 30 a can readily slide along the surfaces of the suture retainer 52 a while the suture retainer moves toward the bone 20 a.

A predetermined tension is maintained in the sections 72 a and 74 a of the suture 38 a while the suture retainer 92 is pressed against the bone 20 a. This results in the suture 38 a being pulled tightly against the suture anchor 50 a. The tension in the suture 38 a is effective to press the suture anchor 50 a and retainer 92 against opposite sides of the bone 20 a with a predetermined force.

Once the suture retainer 92 has been moved along the suture 38 a and is being pressed against the bone 20 a with a predetermined force, the suture retainer is plastically deformed to grip the sections 72 a and 74 a of the suture 38 a. An apparatus 98 for pressing the suture retainer 92 against the bone 20 a includes a tubular cylindrical plunger 102 (FIG. 3) having a cylindrical central passage through which the sections 72 a and 74 a of the suture 38 a extend. The plunger 102 is enclosed by a tubular cylindrical housing 106. The plunger 102 is pressed downward, relative to the housing 106 with a predetermined force, indicated by arrows 108 and 110 in FIG. 3. An annular transducer or load cell 114 provides an output indicative of the magnitude of the force 108 and 110 with which the suture retainer 92 is pressed against the bone 20 a by the plunger 102.

While the sections 72 a and 74 a of the suture 38 a are being tensioned with a predetermined force and while the plunger 102 is being pressed against the suture retainer 92 with a predetermined force, the suture retainer 92 is plastically deformed. To plastically deform the suture retainer 92, a plurality of force applying or clamp members 120 and 122 are pressed against the suture retainer 92 with a predetermined minimum force, indicated schematically by arrows 126 in FIG. 3. The force application members 120 and 122 may have an arcuate configuration to conform to the spherical configuration of the suture retainer 92 or may have a flat configuration. The force applied against the suture retainer 92 by the force applying members 120 and 122 is sufficient to cause plastic deformation of the material of the suture retainer.

The force 126 is applied against the suture retainer 92 while the suture retainer is at a temperature which is below the transition temperature of the biodegradable polymer which forms the suture retainer 92. Thus, the suture retainer 92 is at approximately the same temperature as the bone 20 a when the force 126 is applied against the suture retainer. The force 126 causes the material of the suture retainer 92 to flow and grip the sections 72 a and 74 a of the suture 38 a.

Upon disengagement of the force application members 120 and 122 from the suture retainer 92, the application of downward (as viewed in FIG. 3) force against the suture retainer 92 is interrupted. The upward tensioning of the sections 72 a and 74 a of the suture 38 a is also interrupted. At this time, the plastically deformed suture retainer 92 securely grips the two sections 72 a and 74 a of the suture 38 a to maintain the tension in the suture 38 a. If desired, a knot may be formed between the sections 72 a and 74 a of the suture as additional protection against the suture working loose over an extended period of time.

The suture retainer 92 may be formed of many different materials. However, it is believed that it will be preferred to form the suture retainer 92 of a biodegradable polymer. One biodegradable polymer which may be utilized is polycaperlactone. Alternatively, the suture retainer 92 could be formed of polyethylene oxide terephthalate or polybutylene terephthalate. It is also contemplated that other biodegradable or bioerodible copolymers could be utilized.

Although it is preferred to form the suture retainer 92 of a biodegradable material, the suture retainer could be formed of a material which is not biodegradable. For example, the suture retainer 92 could be formed of an acetyl resin, such as “DELRIN” (trademark). Alternatively, the suture retainer 92 could be formed of para-dimethylamino-benzenediazo sodium sulfonate, such as “DEXON” (trademark). The construction of the suture retainer 92 and the manner in which is cooperates with the suture 38 a is the same as is disclosed in U.S. patent application Ser. No. 08/905,084 filed Aug. 1, 1997 by Peter M. Bonutti et al. and entitled “Method and Apparatus for Securing a Suture”.

The suture retainer 92 is plastically deformed to grip the limbs 72 a and 74 a of the suture 38 a. However, the suture retainer 92 could be constructed so as to be mechanically actuated to grip the suture 38 a. If desired, a combination of a mechanical gripping action and plastic deformation could be utilized by a retainer to grip the suture 38 a.

Retaining Body Tissue Against Bone

In the embodiment of the invention illustrated in FIG. 2, a bone suture assembly 32 is utilized to press surfaces 28 and 30 of a fracture 26 together. In the embodiment of the invention illustrated in FIG. 4, the suture anchor assembly is utilized to hold body tissue against movement relative to a bone. Since the embodiment of the invention illustrated in FIG. 4 is generally similar to the embodiments of the invention illustrated in FIGS. 2 and 3, similar numerals will be utilized in association with similar components, the suffix letter “b” being associated with the numerals of FIG. 4 to avoid confusion.

A cylindrical passage 40 b extends diametrically through a generally cylindrical bone 20 b. A bone suture assembly 32 b is utilized to retain body tissue 132 against movement relative to the bone 20 b. The body tissue 132 may be a muscle, ligament, cartilage or other tissue which is to be held against movement relative to the bone 20 b.

The bone suture assembly 32 b includes a first suture anchor 50 b and a second suture anchor 52 b. A suture 38 b extends through the passage 40 b and interconnects the suture anchors 50 b and 52 b. Tension in the suture 38 b presses the body tissue 132 against a side surface area on the bone 20 b. The suture 38 b has sections or limbs 72 b and 74 b which extends through openings in the suture anchors 50 b and 52 b in the manner previously explained. A knot 78 b interconnects the sections 72 b and 74 b of the suture 38 b to press the suture anchor 52 b firmly against the body tissue 132. Although the illustrated suture has a pair of sections 72 b and 74 b, the suture could have a single section if desired.

The suture anchor assembly 32 b is installed in association with the bone 20 b and body tissue 132 in the same manner as previously explained in conjunction with the embodiment of the invention illustrated in FIG. 2. Thus, the passage 40 (FIG. 4) is formed in the bone 20 b by drilling or other methods. The body tissue 132 may be offset to one side of the location where the passage 40 b is formed during formation of the passage. This enables the passage 40 b to be formed in the bone 20 b without damaging the body tissue 132.

The suture anchor 50 b is moved through the passage 40 b with a longitudinal central axis of the suture anchor aligned with the longitudinal central axis of the passage 40 b. When the suture anchor 50 b emerges from the passage 40 b, the anchor is pivoted to the orientation shown in FIG. 4. Alternatively, the anchor 50 b may be mechanically expanded after emerging from the passage 40 b. A cylindrical tubular member may be used to line the passage 40 a during movement of the anchor 50 b through the passage in the manner previously described in connection with the embodiment of FIG. 2.

After the anchor 50 b has been moved to the position shown in FIG. 4, the body tissue 132 is positioned between the limbs 72 b and 74 b of the suture 38 b. The limbs 72 b and 74 b of the suture 38 b are then inserted through the openings in the suture anchor 52 b. While a predetermined tension is maintained in the suture 38 b, the knot 78 b is tied between the limbs 72 b and 74 b of the suture. This results in the body tissue 132 being pressed against the bone 20 b with a predetermined force. A button or other force distributing member may be provided between the suture anchor 52 b and body tissue 132 if desired.

In the embodiment of the invention illustrated in FIG. 4, two suture anchors 50 b and 52 b are utilized to press the body tissue 132 against the bone 20 b. However, a suture retainer could be substituted for one or more of the suture anchors 50 b or 52 b. For example, a suture retainer having the same construction and installed in the same manner as the suture retainer 92 of FIG. 3 could be substituted for the anchor 52 b of FIG. 4. It should be understood that the suture retainer substituted for the anchor 52 b of FIG. 4 could have any desired construction. Thus, a suture retainer having the construction of any one of the suture retainers disclosed in the aforementioned U.S. patent application Ser. No. 08/905,084 filed Aug. 1, 1997 by Peter M. Bonutti et al. and entitled “Method and Apparatus for Securing a Suture” could be utilized in place of the anchor 52 b and/or the anchor 50 b.

When a suture retainer is used in place of the anchor 52 b, the suture retainer applies force against the body tissue 132 to press the body tissue against the bone 20 b. If desired, a force distribution member could be provided between the suture retainer and the body tissue 132.

Although the passage 40 b has been illustrated in FIG. 4 as having a linear configuration, the passage could have a nonlinear configuration if desired.

In the embodiment of the invention illustrated in FIG. 4, body tissue 132 is disposed adjacent to only one side of the bone 20 b. However, if desired, body tissue could be disposed adjacent to opposite sides of the bone 20 b. The body tissue could be connected with the anchor 50 b in many different ways. For example, a separate length of suture could be connected with the body tissue and anchor 50 b or with the suture 38 b adjacent to the anchor 50 b.

An alternative manner of connecting body tissue with the side of the bone adjacent to the anchor 50 b would be to insert the body tissue between the limbs 72 b and 74 b of the suture 36 b in the same manner as shown with the anchor 52 b. If this is to be done, an end portion of the body tissue may be manually inserted between the limbs 72 b and 74 b of the suture 38 b. If a central portion of the body tissue is to be disposed between the anchor 50 b and the bone 20 b, the connector section 76 b of the suture could be cut. One of the limbs 72 b or 74 b of the suture would then be separated from the anchor 50 b. The body tissue would be inserted between the limbs of the suture 38. The separated end of the suture would then be inserted through the anchor 50 b and connected with the other limb of the suture 38 b.

In the embodiment of the invention illustrated in FIG. 4, the body tissue 132 is pressed against a bone 20 b which has not been fractured. However, it is contemplated that the bone suture assembly 32 could be utilized to perform the dual functions of pressing body tissue against a bone and of pressing opposite side surfaces of a fracture together. This would result in the body tissue being pressed against the bone 20 b in the manner illustrated in FIG. 4 and in opposite side surfaces of a fracture being pressed together in the manner illustrated in FIG. 2 for the opposite side surfaces 28 and 30 of the fracture 26.

Nonlinear Suture Passage

In the embodiment of the invention illustrated in FIG. 2, the passage 40 through which the suture 38 extends has a linear configuration. In the embodiment of the invention illustrated in FIG. 5, the passage through which the suture extends has a nonlinear configuration. Since the embodiment of the invention illustrated in FIG. 5 is generally similar to the embodiment of the invention illustrated in FIGS. 2–4, similar numerals will be utilized to identify similar components, the suffix letter “c” being associated with the components of the embodiment of the invention illustrated in FIG. 5 to avoid confusion.

A bone 20 c as a fracture 26 c which divides the bone into two sections 22 c and 24 c. Opposite side surfaces 28 c and 30 c of the fracture 26 c are pressed together by a bone suture assembly 32 c. The bone suture assembly 32 c includes a suture 38 c which extends between first and second suture anchors 50 c and 52 c.

In accordance with a feature of this embodiment of the invention, the suture 38 c is disposed in a passage 40 c having a nonlinear configuration. Thus, the passage 40 c includes a first section 140 which is skewed relative to a second section 142 of the passage 40 c. A bend 144 is formed in the passage 40 c at an intersection 146 of the first and second sections 140 and 142 of the passage 40 c. The flexible suture 38 c extends around the bend 144 along a nonlinear path between the suture anchors 50 c and 52 c. At the bend 144, the suture 38 c applies force against the section 24 c of the bone 20 c urging the section 24 c toward the left (as viewed in FIG. 5). This force presses the sections 22 c and 24 c of the bone 20 c firmly together at the fracture 26 c.

The suture anchors 50 c and 52 c have the same cylindrical construction as the suture anchors 50 and 52 in the embodiment of the invention illustrated in FIG. 2. A knot 78 c (FIG. 5) is provided between limbs of the suture 38 c to maintain a desired tension in the suture 38 c. This tension pulls the suture anchors 50 c and 52 c toward each other. In addition, this tension presses the section 24 c of the bone 20 c firmly against the section 22 c of the bone at the fracture 26 c.

The first section 140 of the passage 40 c is formed at an angle to and extends through a longitudinal central axis of the generally cylindrical bone 20 c. The second section 142 of the passage 40 c is formed in a direction perpendicular, i.e., along a radius, of the generally cylindrical bone 20 c. The two sections 140 and 142 of the passage 40 c terminate in the spongy cancellous bone tissue 44 c.

When the suture assembly 32 c is to be used to treat the fracture 26 c in the bone 20 c, the two sections 22 c and 24 c of the bone are pressed together at the fracture 26 c to align the side surfaces 28 c and 30 c of the fracture. A drill or other hole forming apparatus is then used to form the first section 140 of the passage 40 c. The drill or other hole forming apparatus is then used to form the second section 142 of the passage 40 c. When the second section 142 of the passage 40 c intersects the first section 140 of the passage 40 c, formation of the section 142 of the passage 40 c is interrupted.

Once the nonlinear passage 40 c has been formed in the two sections 22 c and 24 c of the bone 20 c, a tubular cylindrical liner (not shown) is inserted into the passage 40 c. The tubular cylindrical liner may be formed by two separate tubular members which are inserted at opposite ends of the passage 40 c. Alternatively, the tubular cylindrical liner may be formed by a single flexible tubular member which is inserted into the section 140 of the passage 40 c and then moved around the bend 144 into the section 142 of the passage 40 c. It should be understood that the tubular cylindrical liner for the passage 40 c could be omitted if desired.

The cylindrical anchor 50 c, with the suture 38 c connected thereto, is then positioned in axial alignment with the section 142 of the passage 40 c. The leading end 58 c of the anchor 50 c is then moved into the lined section 142 of the passage 40 c. A flexible pusher member applies force against the trailing end 60 c of the anchor 50 c and pushes the anchor around the bend 144 and through the section 140 of the passage 40 c.

Alternatively, a flexible wire or other member could be inserted into the section 140 of the passage 40 c. The wire would move around the bend 144 and extend outward from the section 142 of the passage. The wire would then be connected with the anchor 50 c and suture 38 c. The leading end 58 c of the anchor 50 c would then be inserted into the section 142 of the passage 40 c. Tension on the wire would pull the anchor 50 c around the bend 144 and out of the section 140 of the passage 40 c.

Once the anchor 50 c has been moved out of the passage 40 c, the tubular liner for the passage may be withdrawn. If a one-piece tubular liner is used, it may be withdrawn from the open end of the section 142 of the passage 40 c. If a two-piece liner is used, one of the pieces may be withdrawn from the open end of the passage section 140 and slit to clear the suture 38 c. Alternatively, the slit could be formed in the piece of the liner before it is inserted into the passage section 140. The other piece of the liner would be withdrawn from the open end of the passage section 142. Alternatively, the tubular liner for the passage 40 c may be left in place. Of course, the use of a tubular liner for the passage 40 c may be omitted.

The suture 38 c is then threaded through openings in the suture anchor 52 c. The suture 38 c is then tensioned and the second anchor 52 c is pressed against the outer side surface of the bone 20 c. While a predetermined tension force is maintained in the suture 38 c, the knot 78 c is tied.

In the illustrated embodiment of the invention, the two sections 140 and 142 of the passage 40 c have a straight cylindrical configuration. However, it is contemplated that the sections 140 and 142 of the passage 40 c could have a different configuration if desired. For example, the section 140 and/or 142 of the passage 40 c could have a nonlinear central axis and could have a noncircular cross-sectional configuration of desired.

Body tissue, corresponding to the body tissue 132 of FIG. 4 could be disposed between the anchor 50 c and/or 52 c and the bone 20 c. Although the suture 38 c has been illustrated as having a pair of limbs or sections which extend between the anchors 50 c and 52 c, the suture 38 c could have a single limb or section if desired. The anchor 50 c could mechanically expand, by absorbing body liquid or under the influence of expansion springs, after the anchor has emerged from the passage 40 c to prevent the anchor from being pulled back through the passage.

Nonlinear Passage—Second Embodiment

In the embodiment of the invention illustrated in FIG. 5, the bone suture assembly 32 c associated with the nonlinear passage 40 c includes a pair of suture anchors 50 c and 52 c. In the embodiment of the invention illustrated in FIG. 6, a suture retainer in substituted for one of the suture anchors in much the same manner as previously described in conjunction with the embodiment of the invention illustrated in FIG. 3. Since the embodiment of the invention illustrated in FIG. 6 is generally similar to the embodiment of the invention illustrated in FIGS. 2–5, similar numerals will be utilized to designate similar components, the suffix letter “d” being associated with the numerals of FIG. 6 in order to avoid confusion.

A bone 20 d has a fracture 26 d which divides the bone into two sections 22 d and 24 d. The fracture 26 d has side surfaces 28 d and 30 d which are pressed together by a bone suture assembly 32 d. The bone suture assembly 32 d includes a suture 38 d which extends through a nonlinear passage 40 d having the same construction as the nonlinear passage 40 c of FIG. 5.

In accordance with a feature of this embodiment of the invention, the bone suture assembly 32 d includes a suture anchor 50 d having the same construction as the suture anchor 50 of FIG. 2, and a suture retainer 92 d having the same construction as the suture retainer 92 of FIG. 3. The suture anchor 50 d and suture retainer 92 d maintain a predetermined tension in the suture 38 d. This results in the suture anchor 50 d being firmly pressed against the section 24 d of the bone 20 d. The suture retainer 92 d is firmly pressed against the section 22 d of the bone 20 d by the tension in the suture 38 d.

Since the passage 40 d has a nonlinear configuration, the suture 38 d is effective to apply a force component to the section 24 d of the bone 20 d urging the section 24 d of the bone toward the left (as viewed in FIG. 6). This results in the surface 30 d of the fracture 26 d being pressed firmly against the surface 28 d of the fracture.

The suture retainer 92 d is plastically deformed to grip the suture 38 d in the same manner as previously described herein in conjunction with the suture retainer 92 of FIG. 3. However, the suture retainer 92 d could be constructed so as to form a mechanical connection with the suture 38 d. If desired, a suture retainer could be substituted for the anchor 50 d.

Although both the suture retainer 92 d and anchor 50 d have been illustrated in FIG. 6 as being disposed in engagement with the bone 20 d, a force distributing member could be provided between the anchor and/or suture retainer and the bone. It is contemplated that body tissue, similar to the body tissue 132 of FIG. 4, could be disposed between the anchor 50 d and/or the suture retainer 92 d and the bone 20 d.

Tissue Tensioning With Bone Fragment Retaining

In the embodiment of the invention illustrated in FIG. 2, the fracture in a portion of a bone is treated. In the embodiment of the invention illustrated in FIGS. 7 and 8, a fracture results in a fragment of a bone being separated from a main portion of the bone. The bone fragment is connected with the main portion of the bone by muscle, tendon, ligament, cartilage or other fibrous body tissue. In the embodiment of the invention illustrated in FIGS. 7 and 8, the fibrous body tissue is tensioned as the bone fragment is positioned relative to the main portion of the bone. Since the embodiment of the invention illustrated in FIGS. 7 and 8 is generally similar to the embodiment of the invention illustrated in FIGS. 2–6, similar numerals will be utilized to designate similar components, the suffix “e” being associated with the numerals of FIGS. 7 and 8 in order to avoid confusion.

A bone fragment 154 is separate from a main bone 20 e (FIG. 7). The fragment 154 is connected with the main bone 20 e by fibrous body tissue 158, i.e., muscle, tendon, ligament, cartilage, etc. The fibrous body tissue 158 extends between the bone fragment 154 and a portion 160 of the main bone 20 e. The bone fragment 154 has a side surface 28 e with a configuration which matches the configuration of a side surface 30 e of a fracture 26 e which occurred in the main bone 20 e.

In order to promote healing of the main bone 20 e, a bone suture assembly 32 e (FIG. 8) is utilized to pull the bone fragment 154 toward the main bone 20 e. As this occurs, the fibrous body tissue 158 is tensioned and the side surface 28 e on the bone fragment 154 is pressed against the side surface 30 e on the main bone 20 e. The bone fragment 154 is pressed firmly against the main bone 20 e by the bone suture assembly 32 e. Thus, the gap illustrated schematically in FIG. 8, between the side surfaces 28 e and 30 e of the fracture 26 e, is eliminated and the side surfaces of the fracture are pressed firmly together by the bone suture assembly 32 e. If desired, the bone fragment 154 may be manually pressed against the main bone 20 e before the bone suture assembly is pulled tight.

The bone suture assembly 32 e includes a suture 38 e having limbs or sections 72 e and 74 e. The suture 38 e extends through openings in a first suture anchor 50 e. The suture then extends into a passage 40 e formed in the bone fragment 154 and the main bone 20 e.

The passage 40 e includes a first section 140 e which extends through the bone fragment 154. In addition, the passage 40 e includes a second section 142 e which extend through the main bone 20 e. The limbs or section 72 e and 74 e of the suture 38 e extends through a second anchor 52 e.

During installation of the bone suture assembly 32 e, the limbs 72 e and 74 e of the suture 38 e are gripped by a force or tension measurement device 98 e. The tension measurement device 98 e includes a load cell which measures the amount of tension applied to the limbs 72 e and 74 e of the suture 38 e.

As tension is applied to the limbs 72 e and 74 e of the suture 38 e, the bone fragment 154 is pulled toward the right (as viewed in FIG. 8) to move the side surface 28 e on the bone fragment into alignment with the side surface 30 e on the main bone 20 e. As this occurs, the fibrous body tissue 158 is stretched or tensioned. While a predetermined force is transmitted through the limbs 72 e and 74 e to the suture anchor 50 e and the bone fragment 154 to firmly press the bone fragment against the main bone 20 e, a knot 78 e is tied to interconnect the limbs 72 e and 74 e. While the predetermined tension is maintained and the knot 78 e tied, the second anchor 52 e is firmly pressed against the side surface of the main bone 20 e.

Although the passage 40 e could have a linear configuration if desired, in the embodiment of the invention illustrated in FIG. 8, the passage 40 e has a nonlinear configuration. Thus, the first section 140 e of the passage 40 e has a central axis which is skewed relative to a central axis of the second section 142 e of the passage 40 e. This enables the flexible suture 38 e to apply force to the bone fragment 154 having components urging the bone fragment rightward (as viewed in FIG. 8) against the surface 30 e on the main bone 20 e and downward (as viewed in FIG. 8) to maintain the tension in the fibrous body tissue 158.

When the passage 40 e is to be formed in the bone fragment 154 and main bone section 20 e, a hole is drilled through the bone fragment 154 to form the first section 140 e of the passage. The second portion 142 e of the passage 40 e is drilled in the main bone 20 e. It should be understood that the passage 40 e could be formed in many different ways other than drilling. For example, a cutting tool or laser could be used to form the passage 40 e.

The second section 142 e of the passage 40 e has a longitudinal central axis which is skewed at an acute angle relative to the longitudinal central axis of the first section 140 e of the passage in the bone fragment 154. Thus, the first portion 140 e of the passage 40 e in the bone fragment 154 has a central axis which is close to being perpendicular to a longitudinal central axis of the main bone 20 e. The second portion 142 e of the passage 40 e has a longitudinal central axis which is angularly offset to a substantial arc relative to the longitudinal central axis of the main bone 20 e.

The anchor 50 e is moved through the first section 140 e of the passage 40 e and positioned in engagement with an outer side surface of the bone fragment. The free ends of the limbs 72 e and 74 e of the suture 38 e are then moved rightward (as viewed in FIG. 8) through the second portion 142 e of the passage 40 e. The free ends of the suture 38 e are then threaded through openings in the second anchor 52 e.

After the suture 38 e has been inserted through openings in the second anchor 52 e, the force or tension measuring device 98 e is utilized to pull the free ends of the suture 38 e toward the right (as viewed in FIG. 8). This tension pulls the bone fragment 154 into engagement with the main bone 20 e. The knot 78 e is tied in the free ends of the suture 38 e while the tension is maintained in the suture.

If desired, the bone suture assembly 32 e could be positioned relative to the bone 20 e and the bone fragment 154 by moving the anchor 50 e first through the second section 142 e of the passage disposed in the main bone 20 e and then through the first section 140 e of the passage disposed in the fragment 154. The free ends of the suture would then be inserted through the second anchor 52 e. The suture 38 e would be tensioned to pull the bone fragment 154 into place with the side surface 28 e in aligned engagement with the surface 30 e on the main bone 20 e. The knot 78 e would then be tied while maintaining the desired tension in the suture 38 e.

It should be understood that the anchor 52 e and knot 78 e could be positioned adjacent to the bone fragment 154 and the anchor 50 e positioned adjacent to the bone 20 e. Although only a single bone suture assembly 32 e has been illustrated in FIG. 8, multiple bone suture assemblies could be used to position the bone fragment 154 relative to the bone 20 e.

In the embodiment of the invention illustrated in FIGS. 7 and 8, the bone suture assembly 32 e includes a pair of anchors 50 e and 52 e. If desired, a suture retainer could be substituted for either or both of the anchors 50 e and 52 e. Thus, a suture retainer having a construction similar to the construction of the suture retainer 92 of FIG. 3 could be used in place of the second anchor 52 e. It should be understood that the suture retainer 92 could have the same construction as any one of the suture retainers disclosed in the aforementioned U.S. patent application Ser. No. 08/905,084 filed Aug. 1, 1997 by Peter M. Bonutti et al. and entitled “Method and Apparatus for Securing a Suture”.

In the embodiment of the invention illustrated in FIG. 8, the anchors 50 e and 52 e are placed in engagement with the bone of fragment 154 and main bone 20 e. However, it is contemplated that the anchor 50 e and/or 52 e could be positioned in engagement with body tissue other than bone. For example, the anchor 50 e could be positioned in engagement with a portion of the fibrous body tissue 158 to position the fibrous body tissue 158 relative to the bone fragment 154 and to more securely interconnect the fibrous body tissue and the bone fragment. If desired, body tissue could be positioned between the anchor 52 e and the main bone 20 e.

In FIG. 8, there is a single bone fragment 154. However, fractures may occur in such a manner as to have a plurality of bone fragments. A plurality of bone suture assemblies 32 e could be utilized to interconnect the plurality of bone fragments and the main bone.

When a fracture occurs in such a manner as to form a plurality of bone fragments, it may be desired to use bone suture assemblies 32 e in association with only the larger bone fragments. If desired, a bridge or cover member could extend across the bone fragments to position the bone fragments relative to each other. One or more bone suture assemblies 32 e would extend through one or more of the larger bone fragments and through the bridge or cover member. Force applied against the bridge or cover member by an anchor or anchors in a bone suture assembly or assemblies 32 e would urge the bridge or cover member toward the main bone 20 e to position the smaller bone fragments relative to the larger bone fragments and main bone 20 e and to press the bone fragments against each other and against the main bone.

One or more of the anchors 50 e and 52 e could be formed of body tissue or of material which absorbs body fluid and expands. Alternatively, one or more of the anchors 50 e or 52 e could be mechanically expanded to block movement into the passage 50 e.

Bone Fragment Retention

In the embodiment of the invention illustrated in FIG. 2, the bone suture assembly 32 extends between diametrically opposite outer side surface areas on the bone 20. This results in the first suture anchor 50 being disposed against an outer side surface of the hard outer layer 42 of the bone 20 (FIG. 1) and the suture anchor 52 being disposed against the outer side surface of the hard outer layer 42 on the opposite side of the bone. In the embodiment of the invention illustrated in FIG. 9, one of the anchors is disposed within the bone and the other anchor is disposed outside of the bone. Since the embodiment of the invention illustrated in FIG. 9 is generally similar to the embodiment of the invention illustrated in FIGS. 2–8, similar numerals will be utilized to identify similar components, the suffix letter “f” being associated with the numerals of FIG. 9 in order to avoid confusion.

A bone 20 f has a hard outer layer 42 f which encloses spongy cancellous bone tissue 44 f. A fragment 164 has broken away from the hard outer layer 42 f. A bone suture assembly 32 f is used to position and hold the fragment 164 in engagement with the bone 20 f. The bone suture assembly 32 f includes a first suture anchor 50 f which is disposed in engagement with an inner side surface 166 of the outer layer 42 f of bone. A second anchor 50 f is disposed in engagement with an outer side surface 168 of the fragment 164. A suture 38 f extends between the first and second anchors 50 and 52 f. The suture 38 f extends through a passage 40 f which extends across a fracture 26 f.

When the bone suture assembly 32 f is used to position the fragment 164 against the outer layer 42 f of the bone 20 f, the fragment 164 is aligned with the outer layer 42 f of the bone 20 f. At this time, a side surface 172 on the fragment 164 is disposed in aligned engagement with a side surface 174 on the bone 20 f. The two side surfaces 172 and 174 were formed by breaking away of the fragment 164 from the outer layer 42 f of the bone.

Once the fragment 164 has been aligned with the bone 20 f, the linear passage 40 f is formed by drilling or other methods through the fragment 164 and the outer layer 42 f of bone. A cylindrical tubular member (not shown) having a thin cylindrical side wall is then inserted through the passage 40 f. The first anchor 50 f is moved to an orientation in which a longitudinal central axis of the first anchor is aligned with a longitudinal central axis of the cylindrical tubular member.

The first anchor 50 f is then moved through the cylindrical tubular member, across the fracture 26 f and into the spongy cancellous bone tissue 44. A pusher member applies force against a trailing end of a first anchor 50 f to push the anchor through the tubular member. When the leading end of the first anchor 50 f emerges from the passage 40 f, the longitudinal central axis of the first anchor is aligned with the longitudinal central axis of the passage 40 f.

The first anchor 50 f is then pivoted through 90 degrees to change its orientation to the orientation shown in FIG. 9. The tubular member is then withdrawn from the passage 40 f. The free ends of the suture 38 f are then inserted through openings in the anchor 52 f. The suture is tensioned to press the anchor 50 f against the inner side surface 166 on the outer layer 42 f of the bone 20 f. The second anchor 52 f is pressed against the outer side surface 168 or the fragment 164 with a predetermined force by the tension in the suture 38 f. A knot 78 f is then tied in the free ends of the suture 38 f to maintain the desired tension in the suture.

Although it is believed that it may be desired to remove the tubular member from the passage 40 f, the tubular member could be left in the passage if desired. If the tubular member is to be left in the passage 40 f, the tubular member may be formed of a biodegradable or bioerodible copolymer. Of course, the use of the tubular member could be eliminated if desired.

It should be understood that a suture retainer, having a construction similar to the construction of the suture retainer 92 of FIG. 3, could be used in place of the second anchor 52 f if desired. Although the suture anchor 52 f has been shown in FIG. 9 as being disposed in direct abutting engagement with the outer side surface 168 of the bone fragment 164, a layer of body tissue could be provided between the suture anchor 52 f and the outer side surface 168 of the bone fragment 164 to hold the body tissue against movement relative to the bone 20 f. If desired, a plurality of bone suture assemblies 32 f could be utilized to hold the bone fragment 164.

Use of Plates With Bone Suture Assembly

In the embodiment of the invention illustrated in FIG. 2, the suture anchors 50 and 52 are disposed in abutting engagement with an outer side surface of a bone. In the embodiment of the invention illustrated in FIG. 10, a pair of bone plates and rigid fasteners are used in association with a bone suture assembly. Since the embodiment of the invention illustrated in FIG. 10 is generally similar to the embodiment of the invention illustrated in FIGS. 2–9, similar numerals will be utilized to designated similar components, the suffix “g” being associated with the numerals of FIG. 10 to avoid confusion.

A bone 20 g has sections 22 g and 24 g which are separated by a fracture 26 g. In accordance with a feature of this embodiment of the invention, a pair of plate members 184 and 186 are used in association with a bone suture assembly 32 g. The plate members 184 and 186 may be formed of any desired biocompatible material. Thus, the plate members may be formed of metal or a polymeric material. If the plate members 184 and 186 are formed of polymeric material, biodegradable or bioerodible copolymers could be utilized.

In the illustrated embodiment of the invention, the plate members 184 and 186 are rigid and are shaped to engage the bone 20 g. If desired, the plate members 184 and 186 could have sufficient flexibility to enable the plate members to be plastically deformed to the configuration of the bone 20 g after having been positioned in engagement with the bone.

A first suture anchor 50 g is pressed against the plate member 184 by tension in a suture 38 g. The suture 38 g extends through a passage 40 g in the bone 20 g. A second anchor 52 g is pressed against the plate member 186 by the tension in the suture 38 g. A knot 78 g is provided in the suture 38 g.

A pair of screws 190 and 192 extend diametrically through the bone 20 g between the plate members 184 and 186. The screws 190 and 192 are engaged by nuts 196 and 198 which engage the plate member 184. The screws 190 and 192 and nuts 196 and 198 cooperate to press the plate members 184 and 186 against the bone 20 g. If desired, bone suture assemblies having the same construction as the bone suture assembly 32 g could be substituted for the screws 190 and 192 and nuts 196 and 198 so that the plates 184 and 186 would be held in position against the bone 20 g by only the plurality of bone suture assemblies 32 g.

The screws 190 and 192 and nuts 196 and 198 may be formed of any desired biocompatible material. Thus, the screws 190 and 192 and nuts 196 and 198 may be formed of metal or a polymeric material. If the screws 190 and 192 and nuts 196 and 198 are formed of polymeric material, biodegradable or bioerodible copolymers could be utilized.

In the illustrated embodiment of the invention, the screws 190 and 192 extend through the bone 20 g. It is contemplated that shorter screws could be utilized if desired. These shorter screws would have relatively coarse bone engaging thread convolutions to hold the short screws and plate members 184 and 186 in place. The shorter screws would have a length which is less than diameter of the bone 20 g.

In the illustrated embodiment of the invention, the bone suture assembly 32 g extends through a linear passage 40 g. If desired, the passage 40 g could have a nonlinear configuration. If bone suture assemblies 32 g are substituted for the screws 190 and 192 and nuts 196 and 198, some of the bone suture assemblies could extend through linear passages while other bone suture assemblies extend through nonlinear passages.

Installation Method

In the embodiment of the invention illustrated in FIG. 2, the passage 40 is formed in the bone 20 by any desired method. A thin walled cylindrical tubular member is then inserted into the passage and the first suture anchor 50 moved through the thin walled member. In the embodiment of the invention illustrated in FIGS. 11 and 12, a cannulated drill is used to drill a passage through a bone and to guide movement of the first anchor through the bone. Since the embodiment of the invention illustrated in FIGS. 11 and 12 is generally similar to the embodiments of the invention illustrated in FIGS. 2–10, similar numerals will be utilized to identify similar components, the suffix “h” being associated with the numerals in FIGS. 11 and 12 to avoid confusion.

A bone 20 h has a fracture (not shown). When the fracture is to be treated with a bone suture assembly 32 h (FIG. 12), a thin elongated cylindrical member or K-wire 204 is first inserted through the bone 20 h. This may be done by rotating the thin elongated member 204 with a drill drive mechanism in the manner indicated by an arrow 206 in FIG. 11. The drill drive mechanism is provided with a passage which extends through a drive shaft for the mechanism. While the thin elongated member 204 is being rotated by the drill drive mechanism, the K-wire extends through the passage in the drill drive mechanism.

As the thin elongated member 204 is rotated by the drill drive mechanism, it is pressed against the bone 20 h. As the thin elongated member 204 is rotated, in the manner indicated by the arrow 206 in FIG. 11, the thin elongated member is moved diametrically through the generally cylindrical bone 20 h until the leading end of the thin elongated member 204 extends from the opposite side of the bone. Thus, the thin elongated member 204 is moved through the hard outer layer 42 h (FIG. 12) at one side of the bone 20 h, through the spongy or cancellous bone tissue 44 h, and through the hard outer layer at the diametrically opposite side of the bone. When this has been done, the thin elongated member 204 will extend across the fracture in the bone.

The drill drive mechanism is then disengaged from the thin elongated member 204. A cannulated drill 210 is moved axially along the thin elongated member until the leading end portion 212 of the drill 210 engages the bone 20 h (FIG. 11). The drill 210 is then gripped by the drill drive mechanism.

While the thin elongated member 204 remains stationary, the drill 210 is rotated about the thin elongated member in the manner indicated by an arrow 214 in FIG. 11. As the drill 210 is rotated about the stationary thin elongated member 204, the drill is moved axially into the bone 20 h. As this occurs, the leading end 212 of the drill enlarges the hole or passage formed in the bone 20 h by the thin elongated member 204. The drill 210 is moved along the thin elongated member 204 until the drill extends diametrically across the bone 20 h. This movement of the drill 210 is guided by engagement of the thin elongated member 204 with a side wall of a cylindrical passage 218 which extends axially through the drill 210. Movement of the drill 210 through the bone 20 h forms a passage 40 h which extends through a fracture in the bone.

Once the drill 210 has been moved diametrically through the generally cylindrical bone 20 h (FIG. 12), the thin elongated member 204 is withdrawn from the drill. This leaves an open cylindrical passage 218 extending through the drill 210 and across the bone 20 h. The passage 218 has a diameter which is just slightly greater than the diameter of a cylindrical first anchor 50 h of the bone suture assembly 32 h. The cylindrical first anchor 50 h is axially aligned with the passage 218 in the drill 210, in the manner shown in FIG. 12. At this time, the suture 38 h has been inserted through openings in the first anchor 50 h and suture limbs or sections 72 h and 74 h extend away from the first anchor 50 h, in the manner indicated schematically in FIG. 12.

A cylindrical pusher member 222 is axially aligned with the first anchor 50 h and the passage 218 through the drill 210. The pusher member 222 is utilized to push the first anchor 50 h through the drill 210 to the far side of the bone 20 h.

As the first suture anchor 50 h emerges from the passage 28 in the drill 210, the anchor is pivoted through ninety degrees. This pivotal movement changes the orientation of the anchor 50 h from an orientation in which the longitudinal central axis of the anchor 50 h is aligned with the longitudinal central axis of the passage 218 and drill 210 to an orientation in which a longitudinal central axis of the cylindrical anchor 50 h extends perpendicular to the longitudinal central axis of the passage and drill. The manner in which the anchor 50 h is pivoted is the same as is described in the aforementioned U.S. Pat. Nos. 5,527,343 and 5,534,012.

The pusher member 222 is then withdrawn from the drill 10 and the drill is withdrawn from the passage formed through the bone 20 h. As this occurs, the suture 38 h is tensioned to hold the anchor 50 h in place against the bone 20 h. The drill 210 is then disengaged from the suture 38 h. The free limbs 72 and 74 of the suture 38 h are then inserted through a second anchor corresponding to the anchor 52 in FIG. 2. While a predetermined tension is maintained in the suture 38 h, the suture is tied to hold the second suture anchor, corresponding to the suture anchor 52 in FIG. 2, against the bone 20 h on a side of the bone opposite from the anchor 50 h.

In the foregoing description, the drill 210 has been a rigid drill which has been used to form a linear passage to the bone 20 h. However, it is contemplated that a flexible drill could be utilized to drill a passage through the bone. If this was done, the drill could be guided in such a manner as to form a nonlinear passage in the bone.

The foregoing description of how the passage 40 h is formed has been in conjunction with a bone 20 h having a fracture similar to the fracture 26 of FIG. 2. However, it is contemplated that the thin elongated member 204 and drill 210 could be used to form a passage in a bone which has not been fractured (FIG. 4). The thin elongated member 204 and 210 could be used to form a passage which extends only part way through a bone (FIG. 9).

In the description of the embodiments of the invention illustrated in FIGS. 1–12, the suture 38 (FIG. 2) has a pair of limbs or sections 72 and 74. It is contemplated that the suture 38 could have only a single limb which would be connected at one end with the first anchor 50 and at the opposite end with the second anchor 52. This single limb could either be tied off at the second anchor 52 or gripped by a suture retainer, similar to the suture retainer 92 of FIG. 3.

In the embodiments of the invention illustrated in FIGS. 1–12, the suture 38 has been formed separately from the first suture anchor 50. It is contemplated that the first suture anchor 50 could be formed as one piece with the suture 38. For example, the suture and anchor could be formed as one piece in a manner similar to that disclosed in U.S. Pat. No. 4,669,473 or in U.S. Pat. No. 4,741,330.

The anchors 50 and 52 in the embodiment of FIGS. 2–12 could have any one of many different constructions. For example, the anchors could expand by absorbing body fluid. The anchor 50, which is moved through a passage 40 in the embodiments of FIGS. 2–12, could mechanically expand upon exiting from the passage.

Positioning of Tubular Member

In the embodiment of the invention illustrated in FIG. 13, a tubular member is positioned in the passage which extends through the bone. Since the embodiment of the invention illustrated in FIG. 13 is generally similar to the embodiments of the invention illustrated in FIGS. 1–12, similar numerals will be utilized to designate similar components, the suffix letter “j” being associated with the numerals of FIG. 13 to avoid confusion.

A bone 20 j which has been fractured is illustrated in FIG. 1. The bone 20 j is divided into two sections 22 j and 24 j by a fracture 26 j. Opposite side surfaces 28 j and 30 j of the fracture 26 j are pressed together by bone securing assemblies 32 j.

It should be understood that the bone securing assemblies 32 j may be utilized in the treatment of any one of many different types of fractures. The fractures may or may not result in the formation of one or more bone fragments. In FIG. 13, the bone securing assembly 32 j has been illustrated as interconnecting sections 22 j and 24 j of a complete bone fracture of the spiral type. However, the bone securing assemblies 32 j could be utilized to connect a fragment of a bone to the main portion of the bone from which the fragment was broken off.

The bone securing assembly 32 j (FIG. 13) includes a force transmitting member 38 j which extends across the fracture 26 j. The force transmitting member 38 j may be any one of many different types of force transmitting members. The force transmitting member 38 j may be formed of human or animal body tissue. However, it is presently preferred to use a suture as the force transmitting member 38 j. Therefore, the force transmitting member 38 j will be referred to herein as a suture.

The suture 38 j, that is, the force transmitting member, is disposed in a straight cylindrical passage 40 j which extends diametrically across a generally cylindrical portion of the bone 20 j. The passage 40 j extends through hard compact tissue of an outer layer 42 j of the bone and through spongy or cancellous bone tissue 44 j which is enclosed by the hard outer layer. Although the passage 40 j has a linear configuration, the passage could have a nonlinear configuration if desired.

The suture 38 j extends between a first suture anchor 50 j disposed on one side of the fracture 26 j and a second suture anchor 52 j disposed on the opposite side of the fracture. Tension is maintained in the suture 38 j to press the suture anchors 50 j and 52 j against opposite sides of the bone 201 with a predetermined force. This force presses the side surfaces 28 j and 30 j of the fracture 26 j firmly together to promote healing of the fracture. If desired, buttons or other force distributing members could be provided between the anchors 50 j and 52 j and the bone 20 j. Body tissue could be disposed between the anchors 50 j and 52 j and the bone 20 j.

The suture 38 j and/or suture anchors 50 j and 52 j may be formed of any desired natural or artificial material. For example, the suture 38 j may be formed of either a polymeric material or a metal. The suture 38 j may be biodegradable. Any known suture material may be utilized to form the suture 38 j.

The suture anchors 50 j and 52 j have the same construction. However, the anchor 50 j could have a construction which is different than the construction of the anchor 52 j. The anchor 50 j has a cylindrical outer side surface 56 j which extends between smooth rounded end portions 581 and 60 j. A pair of parallel cylindrical openings 64 j and 66 j extend diametrically through the anchor 50 j. The anchor 50 j is free of sharp corners or projections to avoid cutting or abrading of body tissue disposed adjacent to the anchor.

The suture anchor 50 j is made of a biocompatible material. Suitable materials include stainless steel or titanium, cobalt chrome and other biocompatible metals. Polymeric material may also be used, suitable polymeric materials includes polyethylene, polypropylene, and biodegradable material such as PLA and PGA. It is believed that it may be preferred to form the suture anchors 50 j and 52 j from biodegradable or bioerodible copolymers. If desired, the anchor 50 j could be formed of body material or hydrophilic materials.

It is contemplated that the anchor 50 j may have any desired configuration. For example, the anchor 50 j could have any one of the configurations disclosed in U.S. Pat. No. 5,522,846 issued Jun. 4, 1996 and entitled “Suture Anchor”. Alternatively, the suture anchor 50 j could have the configuration disclosed in U.S. Pat. No. 5,534,012 issued Jul. 9, 1996 and entitled “Method and Apparatus for Anchoring a Suture”.

The cross-sectional size of the anchor 50 j may be such as to enable the anchor to be moved through the passage 40 j. However, the anchor 50 j could have a size and configuration which would prevent movement of the anchor 50 j through the passage 40 j. For example, the anchors 50 j and 52 j could have the same construction as the retainer 92 of FIG. 3.

The length of the anchor 50 j is such as to enable it to span an opening at an end of the passage 40 j and transmit force from the suture 38 j to a substantial area on the outer layer 42 j of the bone 20 j. The length of the anchor 50 j may be approximately three times the diameter of the anchor. It is believed that it will be preferred to form the anchor 50 j in such a manner as to eliminate any sharp corners or projections.

In the illustrated embodiment of the invention, the anchor 50 j has a cylindrical configuration. This particular anchor has an axial length of about two millimeters and a diameter of about one millimeter. The openings 64 j and 66 j have a diameter of about one-half millimeter.

It should be understood that the foregoing dimensions have been set forth herein for purposes of clarity of description and it is contemplated that the size of the anchor 50 j may vary as a function of the size of the bone being treated. Thus, relatively small anchors may be used in association with treatment of small bones in a wrist, hand, foot or ankle of a patient. Relatively large anchors may be used in association with treatment of larger bones in an arm, shoulder, leg or hip of a patient. It should be understood that the bone securing assembly 32 j may be used in conjunction with many different bones other than the specific bones previously mentioned.

Only a single anchor 50 j or 52 j has been shown at opposite ends of the passage 40 j. It is contemplated that a plurality of anchors could be provided at each end of the passage 40 j. For example, a pair of separate or interconnected anchors could be provided in a manner similar to that disclosed in the aforementioned U.S. Pat. No. 5,534,012.

In the embodiment of the invention illustrated in FIG. 13, the suture 38 j has a pair of limbs or sections 72 j and 74 j which extend through the openings 64 j and 66 j in the suture anchors 50 j and 52 j. A connector section 76 j interconnects the two limbs 72 j and 74 j of the suture 38 j and engages a portion of the anchor 50 j. A knot 78 j is formed in the opposite ends of the limbs 72 j and 74 j to interconnect the two limbs of the suture 38 j.

When the knot 78 j is formed, a predetermined tension is present in the limbs 72 j and 74 j of the suture 38 j. This results in the suture anchors 50 j and 52 j being pressed firmly against the bone 20 j with a predetermined force. This predetermined force is maintained during and after tying of the knot 78 j.

When the bone securing assembly 32 j is to be used to treat the fracture 26 j in the bone 20 j, the two sections 22 j and 24 j of the bone are pressed together at the fracture 26 j to align the side surfaces 28 j and 30 j of the fracture. A drill is then used to form the passage 40 j which extends diametrically through the generally cylindrical bone 20 j. Of course, the passage 40 j could be formed by the use of a tool other than a drill. If desired, the passage 40 j could have a noncircular cross-sectional configuration.

Once the passage 40 j has been formed in the two sections 22 j and 24 j of the bone 20 j, a tubular cylindrical member 240 is inserted into the passage 40 j and extends diametrically through the bone 20 j. The leading end 242 of the tubular cylindrical member 240 is aligned with a circular outlet 84 j from the passage 40 j. The opposite or trailing end 244 of the tubular member is aligned with a circular inlet 86 j to the passage 40 j. The tubular member 240 has a thin cylindrical wall which engages the sections 22 j and 24 j of the bone 201. A cylindrical inner side surface of the tubular member 240 defines a cylindrical passage having a diameter which is only slightly less than the diameter of the passage 40 j.

The leading end 242 of the tubular member 240 is disposed in the compact outer layer 42 j of the bone 20 j. Similarly, the trailing end 244 of the tubular member 240 is disposed in the compact outer layer 42 j of the bone 20 j. The tubular member 240 extends across the fracture 26 j and stabilizes the two sections 22 j and 24 j of the bone 20 j. Since the opposite end portions of the tubular member 240 are disposed in the compact outer layer 42 j of the bone 20 j, the tubular member is solidly supported and holds the two sections 22 j and 24 j of the bone 20 j in alignment at the fracture 26 j.

The opposite ends 242 and 244 of the tubular member 240 are axially spaced from a generally cylindrical outer side surface 250 on the bone 20 j. This enables the anchors 50 j and 52 j to be pressed against the outer side surface 250 of the bone 20 j. Therefore, tension forces in the suture 38 j are transmitted through the anchors 50 j and 52 j to the bone 20 j.

By inserting the tubular member 240 into the passage 40 j, the portions of the passage disposed on opposite sides of the fracture 26 j are maintained in alignment. The tubular member 240 may be flexible to enable the tubular member to be inserted into a nonlinear passage 40 j through the bone 20 j. The tubular member 240 may be formed of metal or a polymeric material. If the tubular member 240 is formed of a polymeric material, it may be preferred to form the tubular member from a biodegradable or bioerodible copolymer.

In accordance with one of the features of this embodiment of the invention, the tubular member 240 is formed of bone. By forming the tubular member 240 of bone, tissue growth into the tubular member is promoted. The tubular member 240 may be packed with bone or bone graft. The tubular member 240 may contain bone osteoinductive protein (BMP). Bone growth inducing materials containing apatite compositions with collagen and/or other materials may be utilized. The tubular member 240 may be formed of either human or animal bone.

It is contemplated that it may be preferred to form the tubular member 240 of freeze dried human bone obtained from a cadaver. The freeze dried bone will absorb body fluids. As this occurs, the tubular member 240 will expand and grip the two sections 22 j and 24 j of the bone 20 j. The body fluids will be conducted into bone growth promoting materials contained in the tubular member 240. If desired, antibiotics and/or other medicants may be provided in the bone or bone graft with which the tubular member 240 is packed. Of course, the tubular member 240 may be formed of other materials, such as biodegradable materials, if desired.

The suture 38 j is formed into a loop which extends through the openings 64 j and 66 j in the anchor 50 j. At this time, the suture 38 j has a length which is substantially greater than the length illustrated in FIG. 2. The cylindrical anchor 50 j, with the suture 38 j connected thereto, is then positioned in axial alignment with the tubular member 240 which extends through the passage 40 j. Thus, the anchor 50 j is moved to an orientation in which a longitudinal central axis of the anchor is coincident with the longitudinal central axis of the cylindrical passage 246 in the tubular member 240 which extends through the passage 40 j in the bone 20 j.

The leading end 58 j of the anchor 50 j is then moved into the cylindrical tubular member 240 which forms a liner for the passage 40 j. A pusher member pushes the anchor 50 j from an upper (as viewed in FIG. 13) end 244 of the tubular member 240 along the passage 246 in the tubular member 240 and the passage 40 j in the bone 20 and through the outlet 84 j from the passage. As the anchor 50 j moves through the passages 40 j and 246, the suture 38 j is pulled through the passages by the anchor.

The orientation of the anchor 50 j is then changed from an orientation in which the longitudinal central axis of the anchor 50 j is aligned with the coincident longitudinal central axes of the passages 40 j and 246 to an orientation in which the longitudinal central axis of the anchor 50 j extends generally perpendicular to the longitudinal central axis of the passages 40 j and 246, i.e., the orientation shown in FIG. 13. To pivot the anchor 50 j to the orientation shown in FIG. 13, as the anchor emerges from the outlet 84, the suture 38 j is tensioned. The combination of the tension in the suture 38 j and force applied against the trailing end 60 j of the anchor 50 j by the pusher member causes the anchor to pivot about the trailing end 60 j of the anchor. The pusher member is then withdrawn and the suture 38 j tensioned to move the anchor to the position shown in FIG. 13 in a manner similar to that described in the aforementioned U.S. Pat. Nos. 5,527,343 and 5,534,012.

Although it is believed that it maybe preferred to change the orientation of the anchor 50 j after it has emerged from the passages 40 j and 246, the anchor could be blocked from reentering the passage in other ways if desired. Thus, the anchor could expand after emerging from the passages 40 j and 246. This could be accomplished by having spring biased arms held in a retracted position by engagement of spring biased arms with the inner side surface of the tubular cylindrical member 240 which lines the passage 40 j. Upon emerging from the passages 40 j and 246, the arms would move outward under the influence of spring forces and extend radially outward beyond the edge of the exit from the passage 40 j. If desired, the anchor 50 j could be constructed so as to expand in a manner similar to that disclosed in U.S. Pat. No. 5,397,331 and/or U.S. Pat. No. 4,409,974.

Rather than expanding under the influence of stored energy, such as spring force, the anchor 50 j could expand by absorbing body fluids. Thus, the anchor 50 j may be compressed when it moves through the passages 40 j and 246 and will expand and absorb body fluids after emerging from the passages 40 j and 246. It is contemplated that the anchor 50 j could be constructed so as to expand in any one of the ways disclosed in U.S. patent application Ser. No. 08/699,553 filed Aug. 19, 1996 by Peter M. Bonutti and entitled “Suture Anchor”.

Once the anchor 50 j has been moved through the passage 246, the passage is packed with bone particles and/or bone graft. The bone particles and/or bone graft contains bone growth inducing materials. In addition, the bone particles and/or bone graft may contain medicinal substances along with osteoinductive protein.

The limbs 72 j and 74 j of the suture 38 j are then threaded through openings 64 j and 66 j in the second suture anchor 52 j. The limbs 72 j and 74 j of the suture 38 j are tensioned and the second anchor 52 j is pressed against the outer side surface 250 of the bone 20 j. While a predetermined tension force is maintained in the limbs 72 j and 74 j of the suture 38 j, the knot 78 j is tied in the suture to interconnect the two suture anchors 50 j and 52 j with the suture 38 j. The suture 38 j is then trimmed to the desired length.

Once the knot 78 j has been tied between the limbs 72 j and 74 j of the suture 38 j, the tension in the suture 38 j presses the side surfaces 28 j and 30 of the fracture 26 j together. This pressure between the side surfaces 28 and 30 j of the fracture 26 j is maintained by the suture 38 and suture anchors 50 j and 52 j until the fracture heals. It is believed that it may be preferred to form the suture 38 j and suture anchors 50 j and 52 j of a biodegradable material which, after the fracture 26 j has healed, will dissolve in the patient's body.

The cylindrical tubular member 240 which is inserted into the passage 40 j through the bone 20 j performs the dual functions of lining the inside of the passage 40 j and maintaining the two sections 22 j and 24 j of the bone in alignment. The cylindrical tubular member 240 could have a slot formed in a side wall of the tubular member to facilitate insertion of the tubular member into the passage 40 j. It is contemplated that the cylindrical tubular member 240 could be left in the passage 40 j after the bone securing assembly 32 j has been installed. If the slotted or unslotted cylindrical tubular member 240 is to be left in the passage 40 j, the cylindrical tubular member 240 may be formed of a biodegradable or bioerodible copolymer. When the cylindrical tubular member remains in the passage 40 j, the suture 38 j extends through the tubular member.

Although only a knot 78 j has been shown in FIG. 13 adjacent to the second anchor 52 j, a suture retainer could be provided to further hold the limbs 72 j and 74 j of the suture 38 j. If a suture retainer is to be used in association with the knot 78 j, the suture retainer will be moved along the limbs of the suture 38 j toward the knot before the limbs 72 j and 74 j of the suture are trimmed to the short length shown in FIG. 13. The suture retainer would then be plastically deformed to grip the limbs 72 j and 74 j of the suture 38 j. Thereafter, the suture limbs 72 j and 74 j would be trimmed to a desired length.

Although it is preferred to use a suture as the force transmitting member 38 j, it should be understood that the anchors 50 j and 52 j could be interconnected by other force transmitting members, such as a rod formed of bone. Although the anchors 50 j and 52 j have constructions which enable them to be used with a suture, the anchors could be constructed so as to be used with other types of force transmitting members. For example, the anchors 50 j and 52 j could have thread convolutions to engage thread convolutions on a force transmitting member formed by a rod.

In the embodiment of the invention illustrated in FIG. 13, the member 240 is tubular. However, it is contemplated that a solid member could be used to transmit force to bone on opposite sides of the fracture 26 j. Thus, the member 240 could be a solid cylindrical member formed of bone. The cylindrical member may be formed of freeze dried bone.

When the member 240 is a solid member, the suture or other force transmitting member 38 j is eliminated. The solid member formed of bone becomes the force transmitting member. Anchors, corresponding to the anchors 50 j and 52 j, are connected to opposite ends of the solid member 240 formed of bone. The anchors may have internal thread convolutions which engage external thread convolutions on the solid member 240 formed of bone. Of course, other known connectors could be utilized to connect anchors with opposite ends of the solid member 240 formed of bone.

Nonlinear Suture Passage—Tubular Member

In the embodiment of the invention illustrated in FIG. 13, the passage 40 j through which the suture 38 j extends has a linear configuration. In the embodiment of the invention illustrated in FIG. 14, the passage through which the suture extends has a nonlinear configuration. Since the embodiment of the invention illustrated in FIG. 14 is generally similar to the embodiment of the invention illustrated in FIGS. 1–13, similar numerals will be utilized to identify similar components, the suffix letter “k” being associated with the components of the embodiment of the invention illustrated in FIG. 14 to avoid confusion.

A bone 20 k as a fracture 26 k which divides the bone into two sections 22 k and 24 k. Opposite side surfaces 28 k and 30 k of the fracture 26 k are pressed together by a bone suture assembly 32 k. The bone suture assembly 32 k includes a suture 38 k which extends between first and second suture anchors 50 k and 52 k.

The suture 38 k is disposed in a passage 40 k having a nonlinear configuration. Thus, the passage 40 k includes a first section 140 k which is skewed relative to a second section 142 k of the passage 40 k. A bend 144 k is formed in the passage 40 k at an intersection 146 k of the first and second sections 140 k and 142 k of the passage 40 k. The flexible suture 38 k extends around the bend 144 k along a nonlinear path between the suture anchors 50 k and 52 k. At the bend 144 k, the suture 38 k applies force against the section 24 k of the bone 20 k urging the section 24 k toward the left (as viewed in FIG. 5). This force presses the sections 22 k and 24 k of the bone 20 k firmly together at the fracture 26 k.

The suture anchors 50 k and 52 k have the same cylindrical construction as the suture anchors 50, 52, 50 j and 52 j in the embodiment of the invention illustrated in FIGS. 2 and 13. A knot 78 k (FIG. 14) is provided between limbs of the suture 38 k to maintain a desired tension in the suture 38 k. This tension pulls the suture anchors 50 k and 52 k toward each other. In addition, this tension presses the section 24 k of the bone 20 k firmly against the section 22 k of the bone at the fracture 26 k.

The first section 140 k of the passage 40 k is formed at an angle to and extends through a longitudinal central axis of the generally cylindrical bone 20 k. The second section 142 k of the passage 40 k is formed in a direction perpendicular, i.e., along a radius, of the generally cylindrical bone 20 k. The two sections 140 k and 142 k of the passage 40 k terminate in the spongy cancellous bone tissue 44 k.

When the suture assembly 32 k is to be used to treat the fracture 26 k in the bone 20 k, the two sections 22 k and 24 k of the bone are pressed together at the fracture 26 k to align the side surfaces 28 k and 30 k of the fracture. A drill or other hole forming apparatus is then used to form the first section 140 k of the passage 40 k. The drill or other hole forming apparatus is then used to form the second section 142 k of the passage 40 k. When the second section 142 k of the passage 40 k intersects the first section 140 k of the passage 40 k, formation of the section 142 k of the passage 40 k is interrupted.

Once the nonlinear passage 40 k has been formed in the two sections 22 k and 24 k of the bone 20 k, a tubular cylindrical liner 240 k is inserted into the passage 40 k. The tubular cylindrical liner 240 k is formed by two separate cylindrical tubular members 252 and 254 which are inserted at opposite ends of the passage 40 k. Alternatively, the tubular cylindrical liner 240 k may be formed by a single flexible tubular member which is inserted into the section 140 k of the passage 40 k and then moved around the bend 144 k into the section 142 k of the passage 40 k.

It is believed that it may be preferred to form the tubular members 252 and 254 of bone. The bone forming the tubular members 252 and 254 may be either human or animal bone. The tubular members 252 and 254 may be formed of freeze dried human bone.

The leading end 242 k of the tubular member 252 is disposed in the compact outer layer 42 k of the bone 20 k. Similarly, the trailing end 244 k of the tubular member 254 is disposed in the compact outer layer 42 k of the bone 20 k. The tubular member 252 extends across the fracture 26 k and stabilizes the two sections 22 k and 24 k of the bone 20 k. Since the end portions 242 k and 244 k of the tubular members 252 and 254 are disposed in the compact outer layer 42 k of the bone 20 k, the tubular members are solidly supported and hold the two sections 22 k and 24 k of the bone 20 k in alignment at the fracture 26 k.

The opposite ends 242 k and 244 k of the tubular members 252 and 254 are axially spaced from a generally cylindrical outer side surface 250 k on the bone 20 k. This enables the anchors 50 k and 52 k to be pressed against the outer side surface 250 k of the bone 20 k. Therefore, tension forces in the suture 38 k are transmitted through the anchors 50 k and 52 k to the bone 20 k.

The cylindrical anchor 50 k, with the suture 38 k connected thereto, is then positioned in axial alignment with the section 142 k of the passage 40 k. The leading end 58 k of the anchor 50 k is then moved into the section 142 k of the passage 40 k lined by the tubular member 254. A flexible pusher member applies force against the trailing end 60 k of the anchor 50 k and pushes the anchor around the bend 144 k and through the section 140 k of the passage 40 k lined by the tubular member 252.

Alternatively, a flexible wire or other member could be inserted into the section 140 k of the passage 40 k. The wire would move around the bend 144 k and extend outward from the section 142 k of the passage. The wire would then be connected with the anchor 50 k and suture 38 k. The leading end 58 k of the anchor 50 k would then be inserted into the section 142 k of the passage 40 k. Tension on the wire would pull the anchor 50 k around the bend 144 k and out of the section 140 k of the passage 40 k.

The passages in the tubular members 252 and 254 may be packed with bone particles and/or bone graft. Bone osteoinductive protein (BMP) may be provided in the tubular members. Antibiotics and/or other medicants may be included along with collagen.

The suture 38 k is then threaded through openings in the suture anchor 52 k. The suture 38 k is then tensioned and the second anchor 52 k is pressed against the outer side surface of the bone 20 k. While a predetermined tension force is maintained in the suture 38 k, the knot 78 k is tied.

In the illustrated embodiment of the invention, the two sections 140 k and 142 k of the passage 40 k have a straight cylindrical configuration. However, it is contemplated that the sections 140 k and 142 k of the passage 40 k could have a different configuration if desired. For example, the section 140 k and/or 142 k of the passage 40 k could have a nonlinear central axis and could have a noncircular cross-sectional configuration of desired.

Body tissue, corresponding to the body tissue 132 of FIG. 4 could be disposed between the anchor 50 k and/or 52 k and the bone 20 k. Although the suture 38 k has been illustrated as having a pair of limbs or sections which extend between the anchors 50 k and 52 k, the suture 38 k could have a single limb or section if desired. The anchor 50 c could mechanically expand, by absorbing body liquid or under the influence of expansion springs, after the anchor has emerged from the passage 40 k to prevent the anchor from being pulled back through the passage.

Retainer and Tubular Member

In the embodiment of the invention illustrated in FIG. 13, a pair of suture anchors 50 j and 52 j are connected with the suture 38 j to maintain tension in the suture and pressure against opposite side surfaces 28 j and 30 j of the fracture 26 j. In the embodiment of the invention illustrated in FIG. 15, a suture retainer is used in place of one of the suture anchors. Since the embodiment of the invention illustrated in FIG. 15 is generally similar to the embodiment of the invention illustrated in FIG. 13, similar numerals will be utilized to designate similar components, the suffix letter “m” being associated with the embodiment of the invention illustrated in FIG. 15 to avoid confusion.

A bone 20 m has sections 22 m and 24 m which are separated by a fracture 26 m. The fracture 26 m has side surfaces 28 m and 30 m which are pressed together by a bone suture assembly 32 m. A suture-38 m extends through a cylindrical passage 40 m which extends diametrically through the generally cylindrical bone 20 m. The suture 38 m has a pair of limbs or sections 72 m and 74 m which are connected with a suture anchor 50 m. The suture anchor 50 m has the same construction as the suture anchor 50 of FIG. 2.

Once the passage 40 has been formed in the two tubular sections 22 m and 24 m of the bone 20 m, a tubular cylindrical member 240 m is installed into the passage 40 m and extends diametrically through the bone 20 m. The leading end 242 m of the cylindrical member 240 m is aligned with a circular outlet 84 m from the passage 40 m. The opposite or trailing end 244 m of the tubular member 240 m is aligned with a circular inlet 86 m to the passage 40 m.

The tubular member 240 m has a thin cylindrical wall which engages the sections 22 m and 24 m of the bone 20 m. A cylindrical inner side surface of the tubular member 240 m defines a cylindrical passage 246 m having a diameter which is only slightly less than the diameter of the passage 40 m. The tubular member 240 m is formed of bone. Alternatively, the tubular member 240 m could be formed of a biodegradable material.

The leading end 242 m of the tubular member 240 m is disposed in the compact outer layer 42 m of the bone 20 m. Similarly, the trailing end 244 m of the tubular member 240 m is disposed in the compact outer layer 42 m of the bone 20 m. The tubular member 240 m extends across the fracture 26 m and stabilizes the two sections 22 m and 24 m of the bone 20 m. Since the opposite end portions of the tubular member 240 m are disposed in the compact outer layer 42 m of the bone 20 m, the tubular member is solidly supported and holds the two sections 22 m and 24 m of the bone 20 m in alignment at the fracture 26 m.

The opposite ends 242 m and 244 m of the tubular member 240 m are axially spaced from a generally cylindrical outer side surface 250 m on the bone 20 m. This enables the anchors 50 m and 92 m to be pressed against the outer side surface 250 m of the bone 20 m. Therefore, tension forces in the suture 38 m are transmitted through the anchors 50 m and 92 m to the bone 20 m.

The tubular member 240 m is formed of freeze dried human bone. The tubular member 240 m is packed with bone and/or bone graft. The tubular member 240 m also contains bone osteoinductive protein (BMP). Suitable medicants may be provided in the tubular member 240 m.

A suture retainer 92 m is used in place of the suture anchor 52 of FIG. 2. The suture retainer 92 m (FIG. 15) has a spherical configuration. A cylindrical passage 94 m extends through the center of the spherical suture retainer 92 m. The sections 72 m and 74 m of the suture 38 m extend around the spherical outer side surface of the suture retainer 92 m. Thus, a loop is formed in each of the sections 72 m and 74 m around portions of the suture retainer 92 m.

If desired, the suture retainer 92 m could have a different configuration. For example, the suture retainer 92 m could have an oval or elliptical configuration. Although the passage 94 m has a linear central axis, the passage could have a nonlinear central axis. If desired, a plurality of passages having the same or different configurations could be provided in the suture retainer 92 m.

After the suture 38 m has been inserted through the suture retainer 92 m, the suture retainer 92 m is moved along the sections 72 m and 74 m of the suture 38 m toward the bone 20 m. The suture retainer 92 m is formed as one piece of a polymeric material having a relatively low coefficient friction. Therefore, the two sections 72 m and 74 m of the suture 30 m can readily slide along the surfaces of the suture retainer 52 m while the suture retainer moves toward the bone 20 m.

A predetermined tension is maintained in the sections 72 m and 74 m of the suture 38 m while the suture retainer 92 m is pressed against the bone 20 m. This results in the suture 38 m being pulled tightly against the suture anchor 50 m. The tension in the suture 38 m is effective to press the suture anchor 50 m and retainer 92 m against opposite sides of the bone 20 m with a predetermined force.

While the sections 72 m and 74 m of the suture 38 m are being tensioned with a predetermined force, the suture retainer 92 m is plastically deformed in the same manner as previously described in conjunction with the embodiment of the invention illustrated in FIG. 3. To plastically deform the suture retainer 92 m, a plurality of force applying or clamp members are pressed against the suture retainer with a predetermined minimum force. The force applied against the suture retainer 92 m by the force applying members is sufficient to cause plastic deformation of the material of the suture retainer.

The force is applied against the suture retainer 92 m while the suture retainer is at a temperature which is below the transition temperature of the biodegradable polymer which forms the suture retainer 92 m. Thus, the suture retainer 92 m is at approximately the same temperature as the bone 20 m when the force is applied against the suture retainer. The force causes the material of the suture retainer 92 m to flow and grip the sections 72 m and 74 m of the suture 38 m.

The suture retainer 92 m may be formed of many different materials. However, it is believed that it will be preferred to form the suture retainer 92 m of a biodegradable polymer. One biodegradable polymer which may be utilized is polycaperlactone. Alternatively, the suture retainer 92 m could be formed of polyethylene oxide terephthalate or polybutylene terephthalate. It is also contemplated that other biodegradable or bioerodible copolymers could be utilized.

Although it is preferred to form the suture retainer 92 m of a biodegradable material, the suture retainer could be formed of a material which is not biodegradable. For example, the suture retainer 92 m could be formed of an acetyl resin, such as “DELRIN” (trademark). Alternatively, the suture retainer 92 m could be formed of para-dimethylamino-benzenediaz-o sodium sulfonate, such as “DEXON” (trademark). The construction of the suture retainer 92 m and the manner in which is cooperates with the suture 38 m is the same as is disclosed in U.S. patent application Ser. No. 08/905,084 filed Aug. 1, 1997 by Peter M. Bonutti et al. and entitled “Method and Apparatus for Securing a Suture”.

The suture retainer 92 m is plastically deformed to grip the limbs 72 m and 74 m of the suture 38 m. However, the suture retainer 92 m could be constructed so as to be mechanically actuated to grip the suture 38 m. If desired, a combination of a mechanical gripping action and plastic deformation could be utilized by a retainer to grip the suture 38 m.

CONCLUSION

In view of the foregoing description, it is apparent that the present invention relates to a method of securing sections 22 and 24 of a fractured bone 20. Sections 22 and 24 of a fractured bone 20 are held against movement relative to each other by a force transmitting member, such as a suture 38, which extends through a passage 40 in the bone. The passage 40 in the bone may have a linear or nonlinear configuration. Tension is maintained in the force transmitting member 38 to press surfaces 28 and 30 on the fracture together by securing anchors 50 and 52 or suture retainers 92 to opposite ends of the force transmitting member 38. It is believed that a suture 38 may advantageously be used as the force transmitting member.

A tubular member 240 is positioned in a linear passage (FIGS. 13 and 15) or a nonlinear passage (FIG. 14) through the bone 20. The tubular member 240 extends into portions of the passage 40 on opposite sides of the fracture 26. End portions of the tubular member may be positioned in a compact outer layer 42 of the bone. The tubular member 240 may be formed of bone. The force transmitting member 38 may be formed of bone or other body tissue. 

1. An internal fracture fixation assembly for fixation of a fracture in a bone, the assembly comprising: an implantable first suture retaining member having a body configured and dimensioned to be moveable through a passage in the bone and to be positionable proximate an outer surface of the bone on a first side of the fracture, the body including first and second parallel channels extending therethrough; a suture having first and second portions, the first portion extending through the first channel of the first suture retaining member and the second portion extending through the second channel of the first suture retaining member, at least one of the portions positionable in the passage of the bone; an implantable second suture retaining member having a body configured and dimensioned to be positionable proximate the outer surface of the bone on a second side of the fracture, the body including a first channel extending therethrough for receiving at least one of the first and second portions of the suture, wherein at least one of the suture retaining members is made of a biocompatible metallic material; a tubular member configured and dimensioned to be positionable within the passage of the bone between the first and second suture retaining members, the tubular member having a lumen for receiving at least part of the first and second portions of the suture; and a material within the lumen of the tubular member, the material selected from the group consisting of bone particles, bone graft, bone growth inducers, medicinal substances, osteoinductive protein, collagen, and combinations thereof, wherein the first channel of the body of the second suture retaining member receives the first portion of the suture and the body of the second suture retaining member includes a second channel extending therethrough for receiving the second portion of the suture, the first and second channels being parallel.
 2. The internal fracture fixation assembly of claim 1 wherein the material within the lumen of the tubular member includes a medicinal substance and the medicinal substance is an antibiotic.
 3. The internal fracture fixation assembly of claim 1 wherein the first suture retaining member is made of a biocompatible metallic material, and the second suture retaining member is made of a biocompatible metallic material.
 4. The internal fracture fixation assembly of claim 1 wherein one of the suture retaining members is biodegradable.
 5. The internal fracture fixation assembly of claim 1 wherein at least one of the suture retaining members includes an expandable material.
 6. The internal fracture fixation assembly of claim 5 wherein the at least one of the suture retaining members expands after being compressed.
 7. The internal fracture fixation assembly of claim 5 wherein the at least one of the suture retaining members expands by imbibing body fluid.
 8. The internal fracture fixation assembly of claim 1 wherein at least one of the suture retaining members includes plastically deformable material to hold the at least one of the suture retaining members to the suture.
 9. The internal fracture fixation assembly of claim 1 wherein the suture is made of a biodegradable material.
 10. The internal fracture fixation assembly of claim 1 wherein the tubular member is made of a biodegradable material.
 11. The internal fracture fixation assembly of claim 10 wherein the tubular member is made of an allograft.
 12. The internal fracture fixation assembly of claim 10 wherein the tubular member has a slit along its length.
 13. An internal fracture fixation assembly for fixation of a fracture in a bone, the assembly comprising: an implantable first suture anchor being configured and dimensioned to be positionable proximate an outer surface of the bone on a first side of the fracture, the first suture anchor including first and second channels extending therethrough; a flexible suture having a first limb, a second limb, and a connector section, the connector section extending through the first and second channels of the first suture anchor, at least one of the first and second limbs positionable in the bone; an implantable second suture anchor being configured and dimensioned to be positionable proximate the outer surface of the bone on a second side of the fracture, the second suture anchor including first and second channels extending therethrough, the first limb of the suture extending through the first channel of the second suture anchor and the second limb of the suture extending through the second channel of the second suture anchor; and a force distributing member positionable between one of the first and second suture anchors and the outer surface of the bone.
 14. The internal fracture fixation assembly of claim 13 further comprising a tubular liner having a lumen for receiving at least a portion of the first and second limbs of the suture.
 15. The internal fracture fixation assembly of claim 13 wherein the force distributing member is a bone plate.
 16. The internal fracture fixation assembly of claim 15 wherein at least a portion of the first and second limbs is extendable through the bone plate and through a passage in the bone.
 17. The internal fracture fixation assembly of claim 16 further comprising a plurality of screws extendable through the bone plate. 